all_in_ruby
Tell your AI coding agents to write scripts in Ruby.
Adds a "write throwaway and utility scripts in Ruby" instruction to agent instruction files - CLAUDE.md for Claude Code, AGENTS.md for Codex. Additive and idempotent: your existing instructions are never modified.
Installation
gem install all_in_ruby
Quick Start
Add the instruction to the current repo:
all-in-ruby install
Or add it globally, for every project:
all-in-ruby install --global
This writes to ~/.claude/CLAUDE.md and ~/.codex/AGENTS.md. If CODEX_HOME is set, it is used instead of ~/.codex, matching Codex's own resolution.
Usage
Target a single agent:
all-in-ruby install --claude
all-in-ruby install --codex
Check where the instruction is installed:
all-in-ruby status
Remove it:
all-in-ruby uninstall
How It Works
The instruction is appended inside marker comments:
<!-- BEGIN all_in_ruby -->
## Scripts
Write throwaway and utility scripts (data munging, one-off migrations,
file renames, glue code) in Ruby — even in projects written in another
language. If it needs a pipe, a loop, a conditional, or more than one
line, it is a script: write it in Ruby, not Python, Node, or bash.
Single self-contained commands (`grep`, `git status`) are fine as-is.
Use only the Ruby standard library. If a gem would clearly save
significant effort, stop and ask before using it.
Put temporary scripts in a scratch or temp directory, not the repo
root, and delete them when done unless asked to keep them.
<!-- END all_in_ruby -->
Existing file content is preserved verbatim. Running install twice is a no-op. uninstall removes only the marked block.
History
View the changelog
Contributing
Everyone is encouraged to help improve this project. Here are a few ways you can help:
- Report bugs
- Fix bugs and submit pull requests
- Write, clarify, or fix documentation
- Suggest or add new features
To get started with development:
git clone https://github.com/lucianghinda/all-in-ruby.git
cd all-in-ruby
bundle install
bundle exec rake test